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Chinese Chemical Letters 2023年第11期34卷 169-174页

作者： Jun-Long li Si-lin Yang qing-Song Dai Hua Huang Lu Jiang qing-zhu li Qi-Wei Wang Xiang Zhang Bo Han Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province Sichuan Industrial Institute of AntibioticsSchool of PharmacyChengdu UniversityChengdu 610106China State Key Laboratory of Southwestern Chinese Medicine Resources School of PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China

Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic ***,we report a multi-component,regioselective bis-acylation of olefins by merging NHC organocatalysis and photoredox *** this protocol,a broad range of 1,4-diketones could be rapidly assembled using bench-stable feedstock *** robustness of this method was further evaluated by sensitivity screening,and good reproductivity was ***,the diketone products could be readily converted into functionalized heterocycles,such as multi-substituted furan,pyrrole,and *** investigations shed light on the NHC and photoredox dual catalytic radical reaction mechanism.

关键词： NHC organocatalysis Photoredox catalysis Radical bis-acylation Multi-component reaction 1,4-Diketone synthesis

Study on Properties of Ti(C,N)/TiN Multi-Element-layer Films Plus Nanometer Lubrication Dry Films

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材料热处理学报 2004年第05B期25卷 909-912页

作者： HUANGYuan-lin MAShi-ning liChang-qing zhuYou-li StateKeyLaboratoryforRemanufacturing Beijing100072China

Ti(C,N)/TiN multi-element-layer films was deposited on aluminium alloy substrates by using multi-arc ion plating. The microhardness of the films was 2000HV0.i which was nearly 21 times of that of the substrates. XRD analysis show that the main composition of the composite films system were Ti(C,N), TiN, Al3Ti, Al and a little Ti2N. The presence of MjTi new phase in the interface of the films/substrates indicated some metallurgical bonding between them, which implies higher adhesive strength of the films/substrates system. Pin-on-disc tests showed that the wear resistance of the substrates was improved substantially. However, the coefficient of friction of the films/substrate system was high (u=0.66), which resulted in the wear of the counterparts. To reduce the coefficient of friction, nanometer lubrication dry films was applied on top of the multi-element-layer films to form composite films system and subsequent wear tests showed that the resulting composite films led to reduction of the coefficient of friction from 0.66 to 0.16. Meanwhile, wear mass loss of the counterpart was reduced from 1.29 mg to 0.02 mg, so that increased wear resistance and reduced friction effects were achieved.

关键词：多电弧离子电镀法铝合金摩擦学纳米薄膜

THE SCHEME FOR THE DATABASE BUILDING AND UPDATING OF 1∶10 000 DIGITAL ELEVATION MODELS

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Geo-Spatial Information Science 2000年第2期3卷 19-25页

作者： zhu qing li Zhilin GONG Jianya SUI Haigang National Laboratory for Information Engineering in Surveying Mapping and Remote Sensing WTUSM

The National Bureau of Surveying and Mapping of China has planned to speed up the development of spatial data infrastructure (SDI) in the coming few *** SDI consists of four types of digital products,i.e.,digital orthophotos,digital elevation models, digital line graphs and digital raster *** the DEM,a scheme for the database building and updating of 1∶10 000 digital elevation models has been proposed and some experimental tests have also been *** paper describes the theoretical (and/or technical) background and reports some of the experimental results to support the *** aspects of the scheme such as accuracy,data sources,data sampling,spatial resolution,terrain modeling,data organization,etc are discussed.

关键词： geospatial data DEM photogrammetric sampling cartographic digitization specification

Electroless copper plating process of N, N, N, N′-tetrakis (2-hydroxypropyl) ethylenediamine system with high plating rate

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Journal of Central South University of Technology 2005年第z1期12卷 82-87页

作者： ZHENG Ya-jie ZOU Wei-hong YI Dan-qing GONG zhu-qing li Xin-hai School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Materials Science and Engineering Central South University Changsha 410083 China School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Metallurgical Science and Engineering Central South University Changsha 410083 China

Electroless copper plating process of N, N, N′, N′-tetrakis (2-hydroxypropyl)ethylenediamine(THPED) chelating agent was researched comprehensively. The results indicate that plating rate decreases with the 3H2O has a bad effect on deposits quality, but 2, 2′-dipyridyl and PEG make deposits quality improve greatly. Low concentration of 2-mercaptobenzothiozole (2-MBT) increases plating rate and improves deposits quality, but decreases plating rate and worsens deposits quality when 2-MBT reaches 5 mg/L. The optimal conditions of this electroless MBT are 16.8 g/L, 16.0 mL/L, 13.3 g/L, 0.5 g/L, 5.0 mg/L and 2.0 mg/L, respectively, pH value is 12.75,bath temperature is 30 ℃. Plating rate reaches 9.54 μm/h plating for 30 min in the bath. The SEM images demonstrate that the surface of copper film is smooth and the crystal is fine.

关键词： electroless copper plating plating rate N, N, N′, N′-tetrakis(2-hydroxypropl) ethylenediamine additive

A compact X-band backward traveling-wave accelerating structure

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Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： Xian-Cai lin Hao Zha Jia-Ru Shi Qiang Gao Fang-Jun Hu qing-zhu li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

Palladium-catalysed stereoselective[3+2]annulation of vinylethylene carbonates and tryptanthrin-based ketones

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Organic Chemistry Frontiers 2022年第1期9卷 197-203页

作者： Yang Fan qing-zhu li Jun-Long li Bin Zhang Zhen Dai Ke Xie Rong Zeng liang Zou Xiang Zhang College of Pharmacy Dali UniversityDali 671003PR China Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province Sichuan Industrial Institute of AntibioticsSchool of PharmacyChengdu UniversityChengdu 610106PR China School of Food and Biological Engineering Chengdu UniversityChengdu 610106PR China

The palladium-catalysed[3+2]annulation of vinylethylene carbonates(VECs)and ketones remains challenging in organic ***,we successfully achieved the[3+2]annulation of tryptanthrin-based ketones and VECs for the efficient synthesis of indoloquinazolinone derivatives with generally excellent yields and good ***,the asymmetric version of this[3+2]annulation can also be achieved by using a chiral spiroketal-based diphosphine *** addition,preliminary biological studies reveal that some of the products exhibit promising antibacterial activity.

关键词： synthesis vinyl Palladium

Design,fabrication,and testing of an X-band 9-MeV standing-wave electron linear accelerator

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Nuclear Science and Techniques 2023年第7期34卷 219-230页

作者： Jian Gao Hao Zha Jia-Ru Shi Qiang Gao Xian-Cai lin Fang-Jun Hu qing-zhu li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

In this study,an X-band standing-wave biperiodic linear accelerator was developed for medical radiotherapy that can accel-erate electrons to 9 MeV using a 2.4-MW *** structure works atπ/2 mode and adopts magnetic coupling between cavities,generating the appropriate adjacent mode separation of 10 *** accelerator is less than 600-mm long and constitutes four bunching cells and 29 normal *** optimizations,full-scale radiofrequency(RF)simulations,and beam dynamics calculations were *** accelerator was fabricated and examined using a low-power RF *** cold test results showed a good agreement with the simulation and actual measurement *** the high-power RF test,the output beam current,energy spectrum,capture ratio,and spot size at the accelerator exit were *** the input power of 2.4 MW,the pulse current was 100 mA,and the output spot root-mean-square radius was approximately 0.5 *** output kinetic energy was 9.04 MeV with the spectral FWHM of 3.5%,demonstrating the good performance of this accelerator.

关键词： Standing-wave accelerating structure RF analysis Thermal DC gun Low-power RF test High-power experiment

Synthesis and Crystal Structure of a Zinc(II) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1271-1275页

作者： YU qing zhu li-Gang BIAN He-Dong DENG Ji-Hua YANG Xiao-E GUO Gui-Quan liANG Hong College of Chemistry and Chemical Engineering Guangxi Normal University Guilin Guangxi 541004 China

The title zinc（Ⅱ） complex salt [Zn（H2O）6]（ClO4）2-（PNOS）4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analysis. It crystallizes in triclinic, space group PI with a = 7.529（3）, b = 10.206（4）, c = 14.678（6）A, a = 86.293（6）, β= 87.686（7）, γ= 81.382（6）°, C28H44Cl2N16O22Zn, Mr = 1093.06, V = 1112.3（8） ,A^3 Z = 1, Dc = 1.632 g/cm^3, S = 1.089, μ（MoKa） = 0.773 mm^-1, F（000） = 564, the final R = 0.0438 and wR = 0.1076 for 3888 independent reflections with Rint = 0.0224. The crystal structure possesses a [Zn（H2O）6]^2＋ cation, two ClO4^- anions and four PNOSs. In the crystal structure, Zn^2＋ cation is located at the symcenter and coordinated by six water molecules. In [Zn（H2O）6]^2＋, an elongate octahedral complex cation, the average Zn-O bond length is 2.087（2） A. There exist a lot of H bonds in the structure, linking the cation [Zn（H2O）6]^2＋, anion ClO4^- and PNOS to form a 3D network.

关键词： zinc(Ⅱ) complex salt picolinaldehyde N-oxide semicarbazone crystal structure,Schiff base

Prognostic role of C-reactive protein in prostate ：ancer： a systematic review and meta-analysis

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Asian Journal of Andrology 2014年第3期16卷 467-471页

作者： zhu-qing liu li Chu Jue-Min Fang Xi Zhang Hua-Xin Zhao Yi-Jing Chen qing Xu Department of Medical Oncology Shanghai Tenth People's Hospital Tongji University School of Medicine Shanghai China.

Several studies have reported that C-reactive protein （CRP）, an inflammation biomarker, may be associated with the prognosis of prostate cancer （PCa）. The objective of this systematic review is to summarize the predictive role of CRP for survival in PCa as reported in previous studies. Related studies were identified, and evaluated for quality through multiple search strategies. Data was collected from studies comparing overall and cancer-specific survival （CSS） in patients with elevated CRP levels and those having lower levels. However, for progression-free survival （PFS）, data were collected according to the log of CRP. The hazard ratio （HR） and its 95% confidence interval （Cl） were used to assess the strength of associations. A total of nine studies （n = 1,497） were evaluated in this meta-analysis （five for overall survival （OS）, four for CSS and two for PFS）. For OS and PFS, the pooled HR of CRP was statistically significant at 1.51 （95% Cl, 1.28-1.79） and 1.50 （95% Cl, 1.25-1.81）, respectively. For CSS, the pooled HR was 1.91 （95% CI, 1.36-2.69） with higher CRP expression in PCa, which strongly indicates poorer survival in PCa. This study demonstrates that CRP may have a critical prognostic value in patients with prostatic cancer.

关键词： C-reactive protein meta-analysis prognosis prostate cancer

Application and mechanism of Fenton-like iron-based functional materials for arsenite removal

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Transactions of Nonferrous Metals Society of China 2022年第12期32卷 4139-4155页

作者： qing-wei WANG Xue-lei YAN Mei-juan MA Ben-sheng li Zong-run li qing-zhu li School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410004China

Between the two major arsenic-containing salts in natural water, arsenite(As(Ⅲ)) is far more harmful to human and the environment than arsenate(As(V)) due to its high toxicity and transportability. Therefore, preoxidation of As(Ⅲ) to As(V) is considered to be an effective means to reduce the toxicity of arsenic and to promote the removal efficiency of arsenic. Due to their high catalytic activity and arsenic affinity, iron-based functional materials can quickly oxidize As(Ⅲ) to As(V) in heterogeneous Fenton-like systems, and then remove As(V) from water through adsorption and surface coprecipitation. In this review, the effects of different iron-based functional materials such as zero-valent iron and iron(hydroxy) oxides on arsenic removal are compared, and the catalytic oxidation mechanism of As(Ⅲ) in heterogeneous Fenton process is further clarified. Finally, the main challenges and opportunities faced by iron-based As(Ⅲ) oxidation functional materials are prospected.

关键词： Fenton-like reaction iron-based functional materials catalytic oxidation arsenic removal